Protein-carbohydrate interactions are now recognized to be important mediators of cell communication. In the last decade many novel carbohydrate binding receptors (CBPs) have been described, several of which have been documented to play critical roles in cell trafficking and cell signaling. Despite these advances the rate at which new information has been generated has been slow, and the biological roles of most mammalian carbohydrate binding proteins are poorly understood. While the importance of this field has attracted many outstanding laboratories, a major barrier to progress has been the additional complexity of the carbohydrates themselves and the analytical and synthetic challenges they pose. The overarching goal of this project is to define the biochemical mechanisms by which protein-carbohydrate interactions mediate cellular events. The project brings together a international multi-institutional and multi-disciplinary group of participating investigators that have a common goal of elucidating the roles of carbohydrate binding proteins in cell communication. Their combined expertise, aided by core resources that are currently unavailable, will dramatically accelerate progress in this emerging frontier.